Cyclobenzaprine Pharmacology


About Cyclobenzaprine
Cyclobenzaprine is a skeletal muscle relaxant and a central nervous system (CNS) depressant. It is structurally similar to Amitriptyline, differing by only one double bond.
Mechanism of Action of Cyclobenzaprine
Cyclobenzaprine is a muscle relaxant.Like other tricyclic antidepressants, cyclobenzaprine exhibits anticholinergic activity, potentiation of norepinephrine, and antagonism of reserpine. Cyclobenzaprine does not directly act on the neuromuscular junction or the muscle but relieves muscle spasms through a central action, possibly at the brain stem level. Cyclobenzaprine acts on the locus coeruleus where it results in increased norepinephrine release, potentially through the gamma fibers which innervate and inhibit the alpha motor neurons in the ventral horn of the spinal cord.Cyclobenzaprine binds to the serotonin receptor and is considered a 5-HT2 receptor antagonist that reduces muscle tone by decreasing the activity of descending serotonergic neurons.
Pharmacokinets of Cyclobenzaprine
1.Absorption: Slowly but well absorbed after oral administration
2.Distribution: Protein binding Very high (93%)
3.Metabolism:Extensively metabolized (gastrointestinal and hepatic)
4.Elimination: Excreted primarily as glucuronides via the kidney, Some unchanged drug is removed in the bile and faeces.

Onset of Action for Cyclobenzaprine
1 hr.
Duration of Action for Cyclobenzaprine
12-24 hr.
Half Life of Cyclobenzaprine
18 hours
Side Effects of Cyclobenzaprine
2.Dry mouth
4.Blurred vision
Contra-indications of Cyclobenzaprine
1.Recent MI
3.Severe liver disease
4.Use with monoamine oxidase inhibitors

Special Precautions while taking Cyclobenzaprine
1.Cardiac disease
2.History of epilepsy
3.Hepatic impairment
6.History of mania
8.Close-angle glaucoma
9.History of urinary retention
10.Concurrent electroconvulsive therapy
12.Unsafe for use in patients with porphyria
13.Avoid abrupt withdrawal
14.May cause drowsiness
15.Do not drive or operate machinery
16.Treatment for more than 2-3 wk is not recommended.
17.Avoid alcohole intake

Pregnancy Related Information
Use with caution
Old Age Related Information
Use with caution
Breast Feeding Related Information
Use with caution
Children Related Information
Use with caution
Indications for Cyclobenzaprine
Adjunct in the short term symptomatic treatment of muscle spasm.
Interactions for Cyclobenzaprine
1.Monoamine oxidase inhibitors taken within 2 weeks of cyclobenzaprine may result in serious, life-threatening side-effects
2.Increased risk of serotonin syndrome when cyclobenzaprine was taken with the serotonergic drugs duloxetine or phenelzine.
3.Plasma concentration may be increased with the use of cimetidine, diltiazem, disulfiram, methylphenidate, ritonavir, and verapamil.
4.Side-effects are increased by adrenaline, amiodarone, general anesthetics, SSRIs, antihistamines, antimuscarinics, antipsychotics, anxiolytics and hypnotics, clozapine, disopyramide, diuretics, flecainide, moclobemide, moxifloxacin, nefopam, nicorandil, noradrenaline, phenothiazine, pimozide, procainamide, propafenone, quinidine, selegiline, sibutramine, sotalol, terfenadine, thioridazine, and tramadol.
5.Effects of adrenergic neurone blockers, clonidine, barbiturates, nitrates, and primidone are reduced
6.Effects of baclofen, opioid analgesics, and thyroid hormones are enhanced with concomitant use of cyclobenzaprine.
7.Carbamazepine and rifampicin may increase metabolism of cyclobenzaprine.
8.Effects may be antagonized by oestrogens.
9. Avoid use with brimonidine, entacapone, artemether with lumefantrine, or sibutramine.
CNS effects may be enhanced by other CNS depressants.

Typical Dosage for Cyclobenzaprine
Adult: PO 5 mg 3 times/day for not >2-3 wk. May increase to 10 mg 3 times/day if needed.
Schedule of Cyclobenzaprine
Storage Requirements for Cyclobenzaprine
Effects of Missed Dosage of Cyclobenzaprine
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at the next regularly scheduled time. Do not take extra medicine to make up the missed dose.

Effects of Overdose of Cyclobenzaprine
1.Seek emergency medical attention if you think you have used too much of this medicine. An overdose of cyclobenzaprine can be fatal.
2.Overdose symptoms may include drowsiness, fast heartbeat, tremors or shaking, slurred speech, confusion, nausea, vomiting, hallucinations, chest pain, or seizure (convulsions).

Home Delivery for Cyclobenzaprine in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including cyclobenzaprine.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for cyclobenzaprine and other medicines and health products. Home delivery services for cyclobenzaprine may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take cyclobenzaprine only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for cyclobenzaprine before they complete the sale. You can get this information while placing the order for cyclobenzaprine with the pharmacy.

Cyclobenzaprine is a generic medicine name and there are several brands available for it. Some of the brands for cyclobenzaprine might be better known than cyclobenzaprine itself. If the pharmacy that's willing to deliver medicines to your home doesn't have cyclobenzaprine in stock, you can ask for one of the branded alternatives for cyclobenzaprine.